scd: New option --debug-assuan-log-cats.

* scd/scdaemon.c (oDebugAssuanLogCats): New.
(opts): Add option --debug-assuan-log-cats.
(main): Implement option.
* common/asshelp.c (set_libassuan_log_cats): New.

--

The old way of setting the logging categories with an environment
variable is awkward if sdaemon is spawned from a running gpg-agent.

common/asshelp.c

@@ -97,6 +97,19 @@ setup_libassuan_logging (unsigned int *debug_var_address)
   assuan_set_log_cb (my_libassuan_log_handler, debug_var_address);
 }
 
+/* Change the Libassuan log categories to those given by NEWCATS.
+   NEWCATS is 0 the default category of ASSUAN_LOG_CONTROL is
+   selected.  Note, that setup_libassuan_logging overrides the values
+   given here.  */
+void
+set_libassuan_log_cats (unsigned int newcats)
+{
+  if (newcats)
+    log_cats = newcats;
+  else /* Default to log the control channel.  */
+    log_cats = (1 << (ASSUAN_LOG_CONTROL - 1));
+}
+
 
 
 static gpg_error_t

common/asshelp.h

@@ -26,6 +26,7 @@
 #include "session-env.h"
 
 void setup_libassuan_logging (unsigned int *debug_var_address);
+void set_libassuan_log_cats (unsigned int newcats);
 
 
 gpg_error_t

doc/scdaemon.texi

@@ -178,7 +178,7 @@ show memory statistics.
 @item 9  (512)
 write hashed data to files named @code{dbgmd-000*}
 @item 10 (1024)
-trace Assuan protocol
+trace Assuan protocol.  See also option @option{--debug-assuan-log-cats}.
 @item 11 (2048)
 trace APDU I/O to the card.  This may reveal sensitive data.
 @end table
@@ -215,6 +215,15 @@ dump.  This options enables it and also changes the working directory to
 @opindex debug-log-tid
 This option appends a thread ID to the PID in the log output.
 
+@item --debug-assuan-log-cats @var{cats}
+@opindex debug-assuan-log-cats
+Changes the active Libassuan logging categories to @var{cats}.  The
+value for @var{cats} is an unsigned integer given in usual C-Syntax.
+A value of of 0 switches to a default category.  If this option is not
+used the categories are taken from the environment variable
+@samp{ASSUAN_DEBUG}.  Note that this option has only an effect if the
+Assuan debug flag has also been with the option @option{--debug}.  For
+a list of categories see the Libassuan manual.
 
 @item --no-detach
 @opindex no-detach

scd/scdaemon.c

@@ -72,6 +72,7 @@ enum cmd_and_opt_values
   oDebugAllowCoreDump,
   oDebugCCIDDriver,
   oDebugLogTid,
+  oDebugAssuanLogCats,
   oNoGreeting,
   oNoOptions,
   oHomedir,
@@ -121,6 +122,7 @@ static ARGPARSE_OPTS opts[] = {
   ARGPARSE_s_n (oDebugCCIDDriver, "debug-ccid-driver", "@"),
   ARGPARSE_s_n (oDebugDisableTicker, "debug-disable-ticker", "@"),
   ARGPARSE_s_n (oDebugLogTid, "debug-log-tid", "@"),
+  ARGPARSE_p_u (oDebugAssuanLogCats, "debug-assuan-log-cats", "@"),
   ARGPARSE_s_n (oNoDetach, "no-detach", N_("do not detach from the console")),
   ARGPARSE_s_s (oLogFile,  "log-file", N_("|FILE|write a log to FILE")),
   ARGPARSE_s_s (oReaderPort, "reader-port",
@@ -553,6 +555,9 @@ main (int argc, char **argv )
         case oDebugLogTid:
           log_set_pid_suffix_cb (tid_log_callback);
           break;
+        case oDebugAssuanLogCats:
+          set_libassuan_log_cats (pargs.r.ret_ulong);
+          break;
 
         case oOptions:
           /* config files may not be nested (silently ignore them) */